Gaseous glow tube controlled musical instrument



h k I 1I w @5K m Lmsum. W N mp M MM W n M A JESS@ H L w w\ v wm. l/ @Qu Btn@ W v Y Qum. Il ,s Il I l. .SEQ hmmm@ NN m. u RSM Q\\ EQ .N\\. N\ wm\ D. M. PARK GASEOUS GLQW TUBE CONTROLLED MUSICAL INSTRUMENT Filed Jan. 15, 1962 Sept. 24, 1963 Yof ten or more instruments United States Patent O ce 3,105,106 GASEOUS GLOW TUBE CONTROLLED MUSICAL INSTRUMENT Donald M. Park, Raleigh, N.C., assignor to Park-Baker Electronic Development Corporation, Raleigh, N.C., a corporation of North Carolina Filed Jan. 15, 1962, Ser. No. 166,159

11 Claims. (ci. srt-1.03)

My invention is concerned with a rhythm control for a musical instrument which generates percussion sounds electronically. vMore speciiically, the invention is concerned with a gaseous glow tube switching device for such an instrument.

One of the more popular electronic musical instruments is known as a side-man and its purpose is to produce percussion rhythms. The side-man is usually comprised such as bass drum, tom toms, blocks, cymbals :and the like which may be electronically combined to produce rhythms such `as the tango, rhumba, fox trot or waltz. The instruments are produced electronically by phase shift oscillators or other noise generators and when played manually or automatically as accompaniment with an electronic organ they produce pleasing repetitive musical effects. Since the side- -man furnishes a concrete example of where my invention may be applied, it is in connection with a sideeman type circuit that my invention is explained.

In prior art side-man devices the switching speed, that is the rhythm speed or tempo, from one instrument to another is controlled by a conventional mechanical variable speed drive. r[his has introduced various wellknown noise and mechanical problems. A conventional wiper 'switch and wiring has been employed with the drive which has required the use of substantially large numbers of brushes, connection wires `and contacts. Due to the number of contacts and various mechanical components required to lproduce conventional rhythms, the prior art side-man systems have further required a relatively large motor drive and Agenerally have not been found 'adaptable to complex rhythms. Since speed control has required a manual mechanical movement the tempo of any particular rhythm has had to remain substantially constant.

A general object of this invention is therefore to provide a considerably improved rhythm control and instrument-selection device for side-man type electronic [musicall circuits. j

Another Objectis to provide a means to electrically pulse instrument generators which gives maximum Alatitude to complex rhythms.

Another object is toprovide a means to electrically pulse instrument generators such that the rhythm tempo may be electrically controlled by the person playing.

"Another object is to provide an instrument selection device which uses gaseous tubes as an integral part of the pulsing circuit so as to substantiallyreduce the lwiring and switching complexity.

Another object is to provide a general electrical pulse selection system which uses gaseous tubes as an integral part of the pulsing circuit soas to substantially reduce the wiring and vswitching complexity.

` These and other objects of the invention will become apparent asy the description proceeds and in the drawings, in which:

n 'FIGURE l1 is a schematic diagram illustrating .the principal componentsA of a side-man system.

' FIGURE 2 is a schematic diagram illustrating an em-.

bodiment of a side-man system according tothe invention. l

FIGURES` is aportion of the diagram of FIGURE 2. FIGURE 4 is a portion of FIGURE 2 with various 2 substitutions illustrating another embodiment of the invention.

Generally speaking, the purpose of a side-man device is to provide a source of repetitive percussion rhythms. The conventional sideman circuit is equipped with means to selectively establish a limited number of both rhythms and tempos. FIGURE 1 illustrates the general system employed. The drive 10 of the conventional system is a constant speed motor |and the speed control 11 consists in practice of a roller which can be moved back and forth along the radius of a disc -driven by the constant speed motor. The roller in turn acts to drive a wiper switch indicated at 12 which through a series of wiper brushes and a considerable number of concentrically arranged contacts serves to selectively transmit pulses from a voltage source indicated at 13 through conventional wiring to any one or combinations of various phase shift oscillators that act `as the designated tone generators 14 and whose output is fed to an amplifier 15 and speaker 16.

In order to be able to change Afrom one rhythm to another in the conventional system .the pulses are yfed through a multi-wafer selector switch 14 that has a movable contact on each wafer subject to a common manual control. By moving the selector switch 17, predetermined circuits can be established between the wiper switch 1.2 contacts and selected tone generators 14. In order to accomplish all of the desired rhythms usually desired, the conventional wiring system necessarily employs several concentric rows of contacts in the wiper switch 12 and a rather complex multi-bank selector switch 17. This is particularly true since the conventional system does not provide iany means to tie the wiper switch contacts into more than one rhythm circuit. The present invention on the other hand provides 'a 'circuit lmeans which allows the wiper switch contacts to appear in a plurality of rhythm circuits fwhile maintaining the contacts in electrical isolation. The present linvention is especially concerned with simplified means flor establishing the speed or tempo, and for establishing circuits between the pulse generator section, that is the wiper switch, and the music section, the tone generators.

Dealing first with the matter of tempo and the diagram of FIGURE A2, the present invention employs a synchronous motor 20 driven by a variable frequency oscillator 21 which is under an appropriate frequency control 22 thereby governing the motor speed and consequently the tempo. The motor 20 may be of the .familiar clock timring motor type since the invention allows a substantial reduction in wiper switch contacts which in turn substantially reduces the wiper switch load that must be driven. A suitable type oscillator is a resistance-capacitance type oscillator with either resistance or capacitance control and in a power class sufficient to meet t-he nominal power required to operate a timing motor. With such an arrangement speed or tempo may be controlled electrically by regulating the position of a resistor or capacitance. Through Iany of several well-known arrangements, the resistor or capacitor positioning may be vadapted for remote operation thereby enabling remote operation of the tempo.

Motor 20 is connected to a wiper switch generally designated rat 23 and drives a constantly rotating 'wiperv tacts will, of course, vary. 'Ilhe wiper switch may ttor example have a much larger number of contacts distributed over several concentric rows and contacted by several brushes. For purposes of simplification, only a limited ',ielectrodes.

number of contacts are shown. It should be pointed out here Ihowever that one of the advantages of the invention prevent lother circuits and tone generators from being activated lby preventing liring `of the tubes even though they are tied into the circuits that are activated. In a ffurther embodiment hereafter described a 2Vs source tand Vs biasing voltages are usedrfor similar purposes.

vTo illustrate how the gaseous tubes lare employed to reduce contactsY `and circuits and to enhance the programming possibilities, three of the wiperswitch contacts are illustrated as they might be wired into an actual side-man simplification, the invention is explained with the use of three tone generators, namely, a drum indicated at 26, blocks indicated at 27 and cymbals indicated 'at 23. The number of tone generators may yvary [and it is not uncommon to find as many as ten separate tone generators in side-man circuits. The outputs of the tone generators are combinedand fed to an lamplilier yas indicated iat 29 and toa speaker as indicated at 30.

Connected to the tone generators is a selector switch generally design-ated at 311and whose purpose is -to .-furnish la manual switching means whereby after the circuits between the wiper switch 23 and selector switch 31 are fixed, the selector switch 31 can be manually moved to various positions so Vas tochiange the particular `tone, generators to which the voltage pulses are directed.l Selector switch 31 is illustrated as comprising three wafers or banks 32,

33 and 34 each ofwhich byway of example has rive contacts land a slider connected `to' respective ones of the tone `genera-tors. For example, it will beseen that the slider for 'bank 32 is connected to the drum 26, the slider for bank 33 is connected to the vblocks 27 and the slider ttor bank 34 is connected to the cymbals 28. It will be understood that the sliders arev physically connected so `that theyA 'change position together andare controllable by a single y manual control knob, Ynot indicated. In this way, the

-at which'they l'are pulsed` will :depend onthe speed of the Ymotor 20 lwhich in turn vwill depend on the setting of the controlling electrical element of frequency control 22. We will now look to whatis one )of the most important aspects of the invention, namely, the manner in which circuits arek made between the pulse generator, the wiper switch, vcontacts and the contactsfeeding the tone generators andY which allows a plurality of connections torbey made to each wiper switch contact.

.An impor-tant aspectl of the circuits between switch and selector switch is the employment of gaseous glow tubes and before proceeding lto .the-actual circuitry, an explanation is rnade of those characteristics ofV these tubes that are of particular interest to theginvention.Y

Examplesv of these tubes j are found in the very inexpensive neon Ne-2 and Ne-96 types. Here, it is important to recognizethat until such a tube breaks down or fires there is near perfect electrical isolation between the tube Another characteristic vof interest is -that the voltage across ,the tube immediately prior to lringfis substantially higher than is the voltage across the tube after the tube has tired. y

ln explanation of the invention, lthe label VS is used to mean the voltage across the tubenecelssary to sustainY ring after the tube has tired. Thus, SVS means three times this vol-tage and ZVSmeans twice this voltage. In the one embodiment illustrated it will be seen that he BtVS-source is used topulse a particulartone'generator through la. particular circuit containing Ygaseous tubes adapted to tire whenv under the influencent this source whereas the. 2Vs sources larefvnsed asr'bias voltagesA to rislfed through suitable tone the wiper circuit. In the selector switch, two typical positions are shown, one in solid lines and *one in dotted lines and as previously mentioned the tone generators are limited to three in number so as to simplify the explanation. While a relatively simple circuit arrangement `of this kind brings `out the invention, it should be appreciated that the inventions greatest advantages lare exhibited in a more com- Y plex circuit sincev more wiper switch contacts, more circuits and more rhythms would [be involved giving more opportunity for the invention to beapplied through circuit simplification. y

Referring to'FIGURE 2, when the selector switch sliders are in the left hand position, indicated in solid lines, the respective instruments will be connected through Atheir respective sliders to the'left band selector switch contacts such as the contacts furthest to therleft inY wafer banks 32, 33, 34. Assuming the selector switch sliders are in such position, circuits are established and `can be traced y between the wiper switch contacts yand the instruments.

Limiting ourselves to contacts 1 and 2 of the wiper switch and the left hand contact of wafer bank 32, we can trace circuits such as illustrated by FIGURE ,3, representing a portion ot kFIGURE 2. f n I 11n FIGURE 3, itV can be seen for example that a circuitbetween the Vs pulse'source and drum 35 is completed when thebrush'25 contacts contact 1 of the wiper switch. This circuit will include gaseous tubes 38 and 39 in series, which are adapted to be red by the 3V5 source so as to cause Ia controlling voltage toi-appear across the input resistor 35. VNow when brush 25 reaches contact 2, it will be seen that a separate circuit to the drum 26 is established which includes 'the previously mentioned gaseous tube 39V and in addition a separate gaseous tube 40 which is selected so as to have a similar jtiring characteristic. From this, it can be seen that contacts 1 and circuits. 'Withsuch a' basic arrangement',"itcan be seen that each of they wiper switch contacts-can actuallyV be tied into several principal circuits and that at least some of the gaseous tubes may appear in a plurality of circuits.

`Reverting back to FIGURE 2, it will be seen that blocks 27 areztied into contacts V1 and 3 of the wiper switch 23. As to contact 1,V the circuit connecti-ng the blocks with the wiper `switch includes gaseous tubes 41.

and 42. AIt is `to be further seen that contact 3- of wiper switch23 is tied into the drum 26 through gaseous tubes 44 and 39 and is tiedinto the cymbals 28; through the gaseous tubes 45 and yed.. and the left hand contact of wafer 34 of'selector switch 31.

y with the `arrangement describedin'FrGUR1-j2,`as the wiper yarm 24 brings brush 25 in contact with contact 1 of wiper switch 23, the 3Vs voltage will pulse circuits to the drum 26 and blocks 2,7 but notthey cymbals '28 even throughthecymbals 'are tied YYinto this contact 1f Y Then as thewiper arm 24: continues to rotate inthe arrow' direction indicated, brush 25 will Y'contact the rcontact 42 whichlwill act to'fpulseV the drum 26 but not the y blocks 27 or cymbalsV 2,8 even though bjoth are tied back into lines which Yconnect with thislcontact 2. `Upon reaching contact 3, all three instruments vwillbe pulsed and accordingly the sound coming out of speaker 3l) will represent a blending of all three tones.

While not shown, it is obvious that each of the eight' wiper switch contacts can be tied into various circuits and can be used to establish circuits in the manner of the circuits explained in connection with the yfirst three con-` tacts. In each instance the electrical contacts in the pulse generator, the wiper switch, are electrically isolated one from the other because there is never enough potential difference to fire .the gaseous tubes along .the secondary path connecting the contacts. Thus, the gaseous tube circuits described serve to direct the pulses alon-g the correct principal paths, to the correct instruments and at the correct times.

"Referring next to the dotted line positions of the wipers in selector `switch 3l, it will be assumed that the selector switch has been rotated so as to bring each wiper to the second contact from the left. Here, the circuits are revised substantially from the circuits previously discussed. For example, with the selector switch wipers in the positions indicated in dotted lines, both contact 1 and contact 2 of the wiper switch when connected to the 3Vs source will act to pulse the drum 26 but no other instrument. Contact 3 when connected to the 3Vs source will pulse the drum 26 and cymbals 28 under this arrangement. To have this change in musical arrangement, it will be noticed that only the short leader connections 47, 48 are required. yIt should further be noticed that the wiper 4switch contacts rem-ain effectively isolated even though tied together and into a plurality of circuits.

A somewhat indirect advantage which has been observed as arising ont of use of gaseous tubes in the manner described is that the invention circuits tend to pulse amplify the applied pulses. Such amplification is accomplished by reason of the difference between breakdown and sustaining voltages of the gaseous tube. This difference appears at the output, the tone generator input, of the network as an increased voltage due to the low impedance input of the pulse source. Accordingly, a sharp and prominent pulse Will appear at each respective tone generator each time a circuit is established between the pulse generator source `and the respective tone generator` In FIGURE 4, there is shown a portion of FIGUREZ with a different glow tube arrangement which4 illustrates a further embodiment of the invention. For purposes of simplifica-tion only portions of the pulse generator and selector switch sections are shown. In the embodiment of FIGURE 4, it will be seen that instead of having two tubes in series in each of the principal paths, only one tube is employed. Accordingly, a lesser pulse voltage indicated as ZVS may be used to open the paths for pulse transmission and a lesser biasing voltage indicated as Vs may be used to block the paths connecting the wiper switch contacts. The reader will understand that the general operation of the one tube per path system is similar to .the previously discussed two tubes per path system with the exception or" the voltages employed and therefore no further detailed discussion is believed necessary.

While a specific form of the invention has been described, it will be understood that variations thereof may be employed without departing from the scope of the invention. For example, other drive and speed control arrangements could be used in combination with the pulse generator section. A multi-vibrator oscillator and various other electrical indexing rotating devices could for example furnish the power and timing requirements of a system employing the glow tube circuits of this invention.

What I claim is:

l. In an electronic music circuit having a plurality of tone generators to be selectively pulsed at given times; a pulse generator including a first set of contacts, a voltage pulse source and means selectively connecting said sounce to said first contacts in predetermined time sequence; switching means including a second' set of contacts connected to respective ones of said tone generators; a network of circuits establishing principal electrical paths from particular rst contacts to particular second contacts and to the respective tone generators connected thereto, portions of said principal paths being in common thereby establishing secondary paths between various pairs of said first contacts; glow discharge tubes placed in each of said paths and adapted to establish said principal paths as pulse transmitting paths responsive to said source and said secondary paths as non pulse transmitting thereby enabling said first contacts to be electrically isolated one from the other while connected to a plurality of said principal paths.

2. In an electronic music circuit as claimed in claim 1 including an additional voltage source continuously biasing said second paths against response to said pulse source.

3. In an electronic music icrcuit as claimed in claim l wherein each of said principal paths includes at least two of said tubes in series.

4. In an electronic music circuit as claimed in claim 1 wherein said switching means includes manual control means allowing each of said tone generators a choice of particular ones of said second contacts to which it is connected thereby enabling said tone generators to be selectively connected to particular ones of said first contacts.

5. In an electronic music circuit as claimed in claim 1 wherein said means for connecting said source to said first contacts comprises a rotating type switch, a synchronous motor drive, a variable frequency drive source and a frequency control for said drive source thereby enabling the tempo of said music to be determined by the setting of said control.

6. In an electroni-c music circuit having a plurality of tone generators to be selectively pulsed at given times; a rotating type pulse generator including a lirst set of contacts, a voltage pulse source, a synchronous motor drive, a variable frequency voltage source for said drive and a frequency control enabling the tempo of said music to be controlled thereby; switching means including a second set of contacts selectively connectable to particular ones of said tone generators; a network of circuits establishing principal electrical paths from particular iirst contacts to particular second contacts, portions of said principal paths being in common thereby establishing secondary paths between various pairs of said first contacts; a plurality of glow discharge tubes placed in each of said paths and adapted to establish said principal paths as pulse transmitting paths responsive to said source and said secondary paths as non pulse transmitting thereby enabling said first contacts to be electrically isolated one from the other while connected to a plurality of said principal paths and voltage biasing means biasing said secondary paths against response to said pulse source.

7. In an electronic circuit having a plurality of electrical devices to be selectively pulsed at given times; a pulse generator including a first set of contacts, a voltage pulse source and means selectively connecting said source to said tirst contacts in predetermined time sequence; switching means including a second set of contacts connected to respective ones of said devices; a network of circuits establishing principal electrical paths from particular first contacts to particular second contacts and to the respective devices connected thereto, portions of said principal paths being in common thereby establishing secondary paths between various pairs of said first contacts; glow discharge tubes placed in each of said paths and adapted to establish said principal paths as pulse transmitting paths responsive to said source `and said secondary paths as non pulse transmitting thereby enabling said first contacts to be electrically isolated one from the other while connected to a plurality of said principal paths.

8. In an electronic cincuit as claimed in claim 7 including an additional voltage source continuously biasing said secondary paths against response to said pulse source.

9. In an electronic circuit as claimed in claim 7 wherein each'of said principal paths includes at least two of said tubes in series.

10. In an electronic circuit as claimed in claim 7 wherein said switching means includes manual control means allowing each of said devices a -choice of particular ones of said second contacts to which it is connected thereby ticular ones of said rst contacts.

D Y Y 0' 1l. In an electronic circuit as claimed in lclaim 7 wherelnrsaid means for connecting said source to said first contacts `comprises a rotating type switch, a synchronous motor drive, a variable frequency drive source and a frequency control for Ysaid drive source thereby enabling the speed of said pulse generator to be determined by the setting of said control.

No references cited;

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 105, 106 September 24, 1963 Donald M. Park It is hereby certified that error appears in the above numbered patreq'liring correction and that the said Letters Patent should read as ent corrected below.

Column 2, line 57, for "capacitance" read capacitor' column 6, line 16, for "second" read secondary line 17, for "crcuit" read circuit Signed and sealed this 7th day of April 1964.

(SEAL) AltSU EDWARD J BRENNER ERNEST W. SWIDER Attesting Ufficer Commissioner of Patents 

1. IN AN ELECTRONIC MUSIC CIRCUIT HAVING A PLURALITY OF TONE GENERATORS TO BE SELECTIVELY PULSED AT GIVEN TIMES; A PULSE GENERATOR INCLUDING A FIRST SET OF CONTACTS, A VOLTAGE PULSE SOURCE AND MEANS SELECTIVELY CONNECTING SAID SOURCE TO SAID FIRST CONTACTS IN PREDETERMINED TIME SEQUENCE; SWITCHING MEANS INCLUDING A SECOND SET OF CONTACTS CONNECTED TO RESPECTIVE ONES OF SAID TONE GENERATORS; A NETWORK OF CIRCUITS ESTABLISHING PRINCIPAL ELECTRICAL PATHS FROM PARTICULAR FIRST CONTACTS TO PARTICULAR SECOND CONTACTS AND TO THE RESPECTIVE TONE GENERATORS CONNECTED THERETO, PORTIONS OF SAID PRINCIPAL PATHS BEING IN COMMON THEREBY ESTABLISHING SECONDARY PATHS BETWEEN VARIOUS PAIRS OF SAID FIRST CONTACTS; GLOW DISCHARGE TUBES PLACED IN EACH OF SAID PATHS AND ADAPTED TO ESTABLISH SAID PRINCIPAL PATHS AS PULSE TRANSMITTING PATHS RESPONSIVE TO SAID SOURCE AND SAID SECONDARY PATHS AS NON PULSE TRANSMITTING THEREBY ENABLING SAID FIRST CONTACTS TO BE ELECTRICALLY ISOLATED ONE FROM THE OTHER WHILE CONNECTED TO A PLURALITY OF SAID PRINCIPAL PATHS. 